Compositions of water-dispersed diprimary amine terminated polymers

ABSTRACT

Novel water-dispersed compositions are prepared containing (1) 100 parts by weight of an amine-containing polymer, (2) at least 25 parts by weight of a solvent which is soluble in both water and organics and has a boiling point above about 100° C., (3) at least about 0.8 equivalent of an organic acid having a pk a  value of less than 5, and (4) from about 50 to about 750 parts by weight of water. The compositions are useful as a component in water-borne resin systems such as epoxies and polyesters.

CROSS-REFERENCE

This is a continuation of U.S. application Ser. No. 07/498,472, filed03/22/90, of Carl Steven Nicols for "COMPOSITION OF WATER-DISPERSEDAMINE-CONTAINING POLYMERS," now U.S. Pat. No. 4,988,461 which in turn isa continuation of Ser. No. 134,385, filed 12/17/87, of Carl StevenNicols, for "COMPOSITION OF WATER-DISPERSED AMINE-CONTAINING POLYMERS,"now abandoned.

BACKGROUND

This invention relates to new compositions of water-dispersed,amine-containing reactive polymers. Polymers of lower molecular weightwhich contain amine groups are known in the art. For example, U.S. Pat.No. 4,133,957 describes amine-terminated liquid polymers represented bythe formula ##STR1## wherein Y is a univalent radical obtained byremoving hydrogen from an amine group of an aliphatic, alicyclic,heterocyclic or aromatic amine containing at least two secondary ormixed primary and secondary amine groups with no more than one primaryamine group per molecule, and "B" is a polymeric backbone comprisingcarbon-carbon linkages. Other amine-containing liquid polymers havingcarbon-carbon linkage backbones and their uses are described in U.S.Pat. Nos. 4,018,847; 4,055,541; 4,058,657; 4,088,708; 4,221,885;4,260,700; and 4,320,047. The B. F. Goodrich Company markets a line ofamine-containing polymers containing carbon-carbon backbone linkagesunder the trademark Hycar® RLP.

Amine-containing polymers are also known which have carbon-oxygenlinkages in the polymeric backbones. An example of this type ofamine-containing liquid polymer is the polyether polyamines described inU.S. Pat. No. 3,436,359. Other examples of amine-containing liquidpolymers having carbon-oxygen backbone linkages backbones and their usesare described in U.S. Pat. Nos. 3,316,185 and 4,521,490. The '490 patentdescribes its amine-containing polymers aspoly(oxyhydrocarbolene)diamines. The Jefferson Chemical Companysubsidiary of Texaco, Inc. markets such amine-containing polymers underthe Trademark Jeffamine® polyoxypropyleneamines.

Amine-containing polymers are useful as components in castableelastomeric systems, as tougheners for epoxy and polyester resins instructural plastics, and in paints, coatings, sealants, adhesives, andthe like.

The amine-containing polymers have, heretofore, been used primarily intheir liquid form or in the form of solvent solutions. However, in manyapplications such as in paints, coatings, sealants, and adhesives, itwould be advantageous to use the polymers in the form of awater-dispersion. A method that can be used to convert amine-containingliquid polymers to water-dispersed compositions involves adding thepolymer to a mixture of water and a high level of soap using a highspeed mixer such as an Eppenbach homogenizer or a Minisonic homogenizerand agitating the mixture under high shear. Such processes requireequipment and time to perform, introduce high levels of soap into thefinal composition, and have not resulted in completely satisfactorywater-dispersed compositions.

SUMMARY OF THE INVENTION

Water dispersed, amine-containing polymer compositions are readilyprepared which comprise a mixture of:

(1) 100 parts by weight of an amine-containing polymer which has anaverage molecular weight from about 1000 to about 10,000,

(2) at least about 25 parts by weight of an organic solvent which isboth water and organic soluble and has a normal boiling point aboveabout 100° C.;

(3) at least about 0.8 carboxyl equivalent of an organic acid for each1.0 amine equivalent, said acid having a pka value of less than about 5;and

(4) from about 50 to about 750 parts of water.

DETAILED DESCRIPTION

Amine-containing polymers which are suitable for use in this inventioncan be represented by the following general formula:

    Y.sub.n --B--X

wherein Y is a univalent radical obtained by removing hydrogen from anamine group of an aliphatic, alicyclic, heterocyclic or aromatic aminewhich has at least two secondary or mixed primary and secondary aminegroups; n is an integer from 1 to about 10; X is either Y or a monomericunit of the polymeric backbone; and B is a polymeric backbone comprisingcarbon-carbon or carbon-oxygen linkages. The polymers used in thisinvention have an average molecular weight of from about 1000 to about10,000; and can be liquids or low melting solids at ambient or roomtemperature (about 25° C.). Generally, the polymeric backbone linkagescomprise at least about 70% by weight and more typically at least about90% by weight of the total polymer, and the amine groups comprise from aminimum of about 0.5% to about 10% or more by weight of the totalpolymer. The polymer can contain pendant amine groups in addition to orin place of terminal amine groups.

Amine-containing polymers such as referenced above are known. Examplesof amine-containing liquid polymers having polymeric backbonescomprising carbon-carbon linkages are described in U.S. Pat. No.4,133,957, which description is hereby incorporated by reference. Suchpolymers are further described in U.S. Pat. No. 4,018,847. Thesepolymers are readily prepared by the reaction of a carboxyl-containingliquid polymer with a diamine or by other methods adequately describedin the above-mentioned patents.

Amine-containing polymers having polymeric backbones comprisingcarbon-oxygen linkages are prepared and described in U.S. Pat. Nos.3,155,728 and 3,436,359, which descriptions are hereby incorporated byreference. Such polymers are further disclosed in U.S. Pat. Nos.3,316,185; 3,654,370; and 4,521,490.

The method of preparing the amine-containing polymers is not critical tothis invention. Any amine-containing polymers meeting the specificationdefined herein can be formed into the water-dispersed compositions ofthe invention using the method described herein.

If the polymers are liquids at room temperature; i.e. about 25° C., thepolymers have a Brookfield viscosity (measured using a Brookfield RVTviscometer at 27° C. with spindle No. 7 at about 20 rpm) of from about200 cps to about 2,500,000 cps, and more preferably from about 500 cpsto about 1,000,000 cps. Polymers which are low-melting solids at roomtemperature, such as those described in U.S. Pat. No. 3,436,359, arealso useful in this invention. These polymers are readily heated up to50° or 60° C. or more to yield a liquid form easily useable in thisinvention.

The amine-containing polymers can have pendant amine groups (i.e., aminegroups which are attached to the polymeric backbone as side groups)and/or terminal amine groups (i.e., amine groups which are attached tothe ends of the polymeric backbone). The amine-terminated polymers canbe mono-functional; i.e. having a primary or secondary amine group atone terminal end of the molecule, or di-functional; i.e. having aprimary and/or secondary amine group at each terminal end of themolecule. Hence, the total amine functionality of the more preferredamine-terminated polymers can range from 1 to about 10 or more, but morepreferably ranges from 1 to about 3 amine groups per molecule.

The amine-terminated polymers having carbon-oxygen linkages in thebackbone have, for the most part, a much wider range of averagemolecular weight and viscosity than the amine-terminated liquid polymershaving carbon-carbon backbones. For example, the polyglycalamine polymersold as Jeffamine® polyoxypropyleneamine D-2000 has an average molecularweight of about 2000, and a viscosity of about 265 centipoises (measuredat 25° C. using a Brookfield RVT viscometer with spindle No. 1 at 20rpm). The polytetramethyleneoxide polymers sold by Minnesota Mining andManufacturing are low-melting solids at room temperature and haveviscosities of up to 100,000 cps at 65° C.

The most preferred amine-containing liquid polymers are theamine-terminated liquid polymers which have polymeric backbonescomprised of carbon-carbon linkages derived from polymerized units of atleast one vinylidene monomer having at least one terminal CH₂ =group.Examples of such vinylidene monomers are (a) monoolefins containing 2 to14 carbon atoms, more preferably 2 to 8 carbon atoms, such as ethylene,propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, andthe like; (b) dienes containing 4 to 10 carbon atoms, more preferably 4to 8 carbon atoms, such as butadiene, isoprene (2-methyl-1,3-butadiene),2-isopropyl-1,3-butadiene, chloroprene (2-chloro-3-butadiene), and thelike; (c) vinyl and allyl esters of carboxylic acids containing 2 to 8carbon atoms such as vinyl acetate, vinyl propionate, allyl acetate, andthe like; and (d) vinyl and allyl ethers of alkyl radicals containing 1to 8 carbon atoms such as vinyl methyl ether, allyl methyl ether, andthe like. Often two or more types of these polymerized monomeric unitsare contained in the polymeric backbone.

The vinylidene monomers described above may be polymerized readily withup to about 50% by weight and more preferably up to about 35% by weightof at least one comonomer selected from the group consisting of (e)vinyl aromatics having the formula ##STR2## wherein R₂ is hydrogen ormethyl and R₃ is hydrogen, halogen or an alkyl radical containing from 1to 4 carbon atoms, such as styrene, α-methyl styrene, chlorostyrene,vinyl toluene, and the like; (f) vinyl nitriles having the formula##STR3## such as acrylonitrile and methacrylonitrile (g) vinyl halidessuch as vinyl bromide, vinyl chloride, and the like; (h) vinyl acidssuch as acrylic acid, methacrylic acid, and itaconic acid; (i) divinylsand diacrylates such as divinyl benzene, divinyl ether, diethyleneglycol diacrylate, and the like; (j) amines of α,β-olefinicallyunsaturated carboxylic acids containing 2 to 8 carbon atoms such asacrylamide, and the like; and (k) allyl alcohol, and the like. Liquidpolymer compositions having polymeric backbone derived from polymerizedunits of a major amount of at least one vinylidene monomer listed in (a)to (d) with a minor amount of at least one comonomer listed in (e) to(k) are within the scope of this invention.

Examples of useful interpolymerized polymeric backbones of carbon-carbonlinkages include polyethylene, polyisobutylene, polyisoprene,polybutadiene, poly(vinyl ethyl ether), as well as polymers of butadieneand acrylonitrile; butadiene and styrene; butadiene, acrylonitrile, andacrylic acid; vinyl acetate and isoprene; and vinyl acetate andchloroprene.

The most preferred liquid amine-terminated polymers are theamine-terminated liquid polymers having polymeric backbones comprised ofcarbon-carbon linkages derived from interpolymerized units of from about50% to about 99.6% by weight of a diene such as isoprene or butadiene,and up to about 40% by weight of a vinyl nitrile such as acrylonitrileor a vinyl aromatic such as styrene, and up to 10% by weight of a vinylacid such as acrylic acid, and having an amine content of from about0.4% to about 10% by weight of the amine groups, all weights based uponthe total weight of the polymer. These polymers have an averagemolecular weight of from about 1000 to about 5000, and a viscosity offrom about 1000 to about 500,000 centipoises (measured at 27° C. using aBrookfield RVT viscometer with spindle no. 7 at 20 rpm).

Another essential ingredient in the composition of this invention is thesolvent. The solvent requires the unusual property of being both waterand organic soluble and having a relatively high boiling point ofgreater than about 100° C. Examples of solvents having the abovedescribed properties include the glycol ethers such as1-methoxy-2-methyl ethanol, 2-propoxyethanol and 2-butoxyethanol whichis commercially sold under the trademark butyl CELLOSOLVE.

The solvent is used in the composition at a level of at least 25 partsby weight based on 100 parts by weight of the polymer. When less than 25parts of solvent is used with 100 parts by weight of polymer, theproduct composition is typically unstable and exhibits two phases. Morepreferably, the solvent is used in the range of about 50 to about 500parts by weight based on 100 parts by weight of the polymer. The upperamount of solvent used is limited basically by the practical feasibilityof the process. Excellent compositions were obtained when employingabout 100 parts by weight of the solvent per 100 parts by weight of theamine-containing liquid polymer.

The third essential ingredient of the composition is an organic acidwhich has a pka value of less than 5. The preferred acids are shortchain organic acids represented by the formula ##STR4## where R^(a) is astraight or branched chain alkyl group containing from about 1 to about9 carbon atoms, and R^(b) is hydrogen, a hydroxyl group or a halogen.The most preferred organic acids are those of the above formula whereinR^(b) is a hydroxyl group. Excellent results were obtained when theorganic acid used was lactic acid.

The amount of organic acid employed is determined by the stoichiometryrelationship of the acid per 1.0 amine equivalent. The amine equivalentweight (AEW) of the polymer is defined as 100 divided by the equivalentsper hundred rubber of the amine-containing polymer. The amine-containingpolymer can be solubilized using as low as about 0.8 carboxylequivalents of organic acid per 1.0 amine equivalent. However, betterdispersion is obtained at a level of about 1.0 carboxyl equivalent oforganic acid per 1.0 amine equivalent, although up to a 20% excess canbe readily employed without problems. The upper level of organic acidused is basically limited by feasibility and cost.

Water is the fourth essential ingredient in the composition. The waterused can be distilled water, demineralized water, or regular tap water.The amount of water used in the solution is in the range of from about50 parts to about 750 parts by weight per 100 parts by weight of thepolymer. More preferably, the amount of water employed is from about 200parts to about 600 parts of water per 100 parts of the polymer.Excellent results were obtained using about 500 parts by weight of waterper 100 parts by weight of amine-containing liquid polymer.

The composition of the water-dispersed, amine-containing polymer isreadily prepared by first dissolving the polymer in the solvent. Thiscan be readily done at ambient temperature or with mild heating in avessel. The dissolution of the polymer in the organic solvent isenhanced by mild agitation with, for example, a propeller type mixeroperating at about 50 to about 300 rpm. Thereafter, the organic acid isadded to the solvent solution of the polymer. Finally, the water isadded slowly with mild agitation to yield a stable suspension of theliquid polymer in the water. No soap is used to prepare thewater-dispersed compositions.

The compositions of the invention containing the water-dispersedamine-containing polymer can be readily used as a component in castableelastomeric systems, as an impact modifier for water-borne epoxy andpolyester resins and coatings, and other applications.

The following examples illustrate the invention described herein. Theexamples are not to be construed as limiting in any way the scope of theinvention disclosed herein.

EXAMPLE 1

A series of experiments were run using an amine-terminated liquidpolymer commercially available from the B. F. Goodrich Company andmarketed as Hycar® ATBN 1300×16. The polymer contains about 16% byweight of acrylonitrile, has a Brookfield viscosity of 200,000 cps at27° C. (81° F.), and has an amine equivalent weight of about 900. Thelactic acid used in the example has a carboxyl equivalent weight of 90.The components used in the recipes below are shown in parts by weight.

    ______________________________________                                                  1       2         3        4                                        ______________________________________                                        ATBN (1300 × 16)                                                                    20        20        20     20                                     Butyl Cellosolve                                                                          20        10        --     20                                     Lactic Acid  3         3         3     --                                     (85% in water)                                                                Water       100       100       100    100                                    Appearance  Translucent                                                                             Opaque    Stiff  Two                                                and Stable                                                                              and Stable                                                                              Emulsion                                                                             Phases                                 ______________________________________                                    

The compositions were prepared by dissolving the ATBN liquid polymer inthe butyl CELLOSOLVE at a temperature of about 25° C. followed byaddition of the lactic acid. Water was then slowly added to thecompositions while agitating the mixture at 50 to 300 rpm using an airstirrer with a marine blade. The first recipe exemplifies a preferredcomposition of the invention wherein a stable, translucent compositionwas prepared. In the second recipe, the use of less solvent (at 50 partsby weight based on 100 parts of liquid polymer) resulted in an opaquebut still stable composition. Recipes 3 and 4 demonstrate thecriticality of using the solvent and the organic acid, respectively, inthe compositions. In both cases, the absence of one of the essentialingredients resulted in a non-stable composition.

EXAMPLE 2

The above experiment was repeated using other amine-terminated liquidpolymers. The polymers are described as follows: AT-RLP-1 has apolybutadiene backbone, a Brookfield viscosity of 127,000 cps. at 27°C., and an amine equivalent weight of 1050; AT-RLP-2 has a backbone ofinterpolymerized butadiene and acrylonitrile (about 10% by weight), aviscosity of 180,000 cps., and an amine equivalent weight of 1200; andAT-RLP-3 has a backbone of interpolymerized butadiene, acrylonitrile(about 16% by weight), and acrylic acid (about 1.7% by weight) whichcarboxyl groups were converted to amine groups using the teachings ofU.S. Pat. No. 4,133,957, a viscosity of 460,000 cps, and an amineequivalent of about 800. The components used in the recipes below areshown in parts by weight.

    ______________________________________                                                  1        2          3                                               ______________________________________                                        AT-RLP-1    20         --         --                                          AT-RLP-2    --         20         --                                          AT-RLP-3    --         --         20                                          Butyl Cellosolve                                                                          20         20         2                                           Lactic Acid  3          3         3                                           Water       100        100        100                                         Appearance  Translucent                                                                              Translucent                                                                              Translucent                                             and Stable and Stable and Stable                                  ______________________________________                                    

EXAMPLE 3

The experiment in Example 2 above was essentially repeated using amono-functional amine-terminated liquid polymer having a polymericbackbone comprised of interpolymerized butadiene and acrylonitrile(about 16% by weight). The amine-terminated polymer has a viscosity of64,000 cps. and an amine equivalent weight of 2500. The recipe used was10 parts by weight of polymer, 10 parts by weight of butyl CERLLOSOLVE,1.5 parts by weight of lactic acid, and 50 parts by weight of water. Astable, translucent composition was readily prepared.

EXAMPLE 4

The above experiments were essentially repeated using anamine-containing liquid polymer having a polymeric backbone comprised ofcarbon-oxygen linkages. The amine-terminated polyether used is known asD-2000, which is commercially available from Texaco, Inc. through itsJefferson Chemical Co. subsidiary. The polymer is apolyoxypropyleneamine which has an average molecular weight of about2000, a viscosity of about 265 centipoises at 25° C., and an amineequivalent weight of 1040. The recipe used was 20 parts by weight ofD-2000, 20 parts by of butyl CELLOSOLVE, 3 parts by weight of lacticacid and 100 parts by weight of water. A stable, translucent compositionwas readily prepared.

EXAMPLE 5

The experiment in Example 4 above was repeated using a higher molecularweight amine-containing polymer having a polymeric backbone comprised ofcarbon-oxygen linkages. The amine-terminated polymer used is known asHC-1101, which is commercially available from the 3M Co. The polymer hasan average molecular weight of 10,000, and an amine equivalent weight of4610. The polymer is a low-melting solid at room temperature. Hence, thepolymer was heated to about 5° C. and used in a liquid state. The recipeused was 10 parts by weight of HC-1101, 10 parts by weight of butylCELLOSOLVE, 1.5 parts by weight of lactic acid and 50 parts by weight ofwater. A stable, translucent composition was readily prepared.

I claim:
 1. A water-dispersed toughening agent composition for castableelastomeric systems, said composition comprising: (1) 100 parts byweight of an amine-containing liquid polymer having an average molecularweight of from about 1000 to about 10,000, (2) at least 25 parts byweight of an organic solvent which is both water and organic soluble andhas a normal boiling point above about 100° C., (3) at least about 0.8carboxyl equivalent of an organic acid for each 1.0 amine equivalent,said acid having a pk_(a) value of less than about 5, and (4) from about50 to about 750 parts by weight of water, wherein said amine-containingliquid polymer is represented by the following general formula:

    Y.sub.n --B--X

wherein Y is a univalent radical obtained by removing hydrogen from anamine group of an aliphatic, alicyclic, heterocyclic or aromatic aminewhich has at least two primary amine groups; n is an integer from 1 toabut 10; X is Y; and B is a polymeric backbone comprising carbon-carbonor carbon-oxygen linkages.
 2. A composition of claim 1, wherein theamine-containing liquid polymer has a polymeric backbone comprised ofinterpolymerized units of from about 50 percent to about 99.6 percent byweight of a diene, up to about 40 percent by weight of a vinyl nitrileor vinyl aromatic, and up to about 10 percent by weight of a vinyl acid,and has an amine content of from about 0.4 percent to about 10 percentby weight, all weights based upon the weight of the polymer.
 3. Acomposition of claim 1, wherein the solvent is present in from about 100to about 500 parts by weight based on 100 parts by weight of thepolymer.
 4. A composition of claim 3, wherein the solvent is2-butoxyethanol.
 5. A composition of claim 1, wherein the organic acidis employed at about 1.0 carboxyl equivalent or organic acid for every1.0 amine equivalent.
 6. A composition of claim 1, wherein the organicacid is lactic acid.